Urinary tract infections (UTIs) are common and generally benign conditions among healthy, sexually active young women without long-term medical sequelae. In contrast, UTIs are more complicated among those individuals at either end of the age spectrum: infants/young children and geriatrics. UTI in children younger than 2 years has been associated with significant morbidity and long-term medical consequences, necessitating an extensive and somewhat invasive imaging evaluation to identify possible underlying functional or anatomic abnormalities. Pediatric UTI should be considered complicated until proved otherwise, and treatment should reflect the severity of signs and symptoms. Management in the acutely ill child frequently involves parenteral broad-spectrum antimicrobial agents, and less ill children can be treated with trimethoprim- sulfamethoxazole (TMP-SMX), β-lactams, and cephalosporins.

UTI among older patients (>65 years) may be complicated by comorbidities, the baseline presence of asymptomatic bacteriuria, and benign urinary symptoms that can complicate diagnosis. The etiology of UTI encompasses a broader spectrum of infecting organisms than is seen among younger patients and includes more gram-positive organisms. Symptomatic UTI is generally more difficult to treat than among younger populations. Management should be conservative, of longer treatment durations, and cover a broad spectrum of possible uropathogens. Oral or parenteral treatment with a fluoroquinolone for 7 days is the preferred empiric approach. TMP-SMX can also be considered a first-line agent in women only, but only if the pathogen is known to be TMP-SMX sensitive.